Biology

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Biology. The study of life. Biology is the study of life!. All living things share the characteristics of life!. Biology covers a wide range of topics and research areas! It is diverse!. Science comes from Latin for “to know” - PowerPoint PPT Presentation

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BiologyThe study of life

Biology is the study of life!• All living things share the characteristics of

life!

Types of observations• Qualitative and Quantitative• What is the difference?

• Qualitative means describing something such as its color, shape or texture= Quality

• Quantitative means using measurements such as its height, mass or volume.= Quantity

Describe these peanuts

• Biologists study the diversity of life

• Research disease

• Develop technology• Improve agriculture• And help preserve the environment

Characteristics of Living Things

• Anything that possesses all of the characteristics of life, or once had them, is known as an organism.

Characteristics of Living Things

All living things:• have an orderly structure• produce offspring• grow and develop

• adjust to changes in the environment

Living Things are made up of one or more cells!

• The cell theory states that the cell is the basic unit of life!

• That means you can’t be smaller than a cell and still be alive!!!

• All living things are made up of cells.• Some are only one cell and some are

billions!

Living things are organized• When biologists search for signs of life, one of

the first things they look for is structure• Whether an organism is made up of one cell or

billions of cells, all of its parts function together in an orderly, living system.

– A cell is the smallest unit of an organism that can perform all life’s processes.

Living things change during their lives

• Growth results in an increase in the amount of living material and the formation of new structures. Increase in mass

• All of the changes that take place during the life of an organism are known as its development. Different abilities result from development.

Living things make more living things

• One of the most obvious of all the characteristics of life is reproduction, the production of offspring.

• This maintains the species so extinction does not occur!

Living things adjust to their surroundings- Respond to Stimuli

• Organisms live in a constant interface with their surroundings, or environment, which includes the air, water, weather, temperature, any other organisms in the area, and many other factors.

• Anything in an organism’s external or internal environment that causes the organism to react is a stimulus.

• A reaction to a stimulus is a response.

Living Things Require Energy!!!

• Energy is required for all living processes!• It helps maintain the organization!• Many organisms take in food while others

make their own this is called their metabolism!

Living things adjust to their surroundings

• Regulation of an organism’s internal environment to maintain conditions suitable for its survival is called homeostasis.

Living things adapt and evolve• Any structure, behavior, or internal process that

enables an organism to respond to environmental factors and live to produce offspring is called an adaptation.

• Adaptations are inherited from previous generations. These are not acquired during the organism’s lifetime but inherited!

• The gradual change in a species through adaptations over time is evolution.

Three Domains of Life

– The three domains of life are Bacteria, Archaea, and Eukarya.

– The six kingdoms include Archaea, Bacteria, Protista, Fungi, Plantae, and Animalia.

All living things have an orderly structure, produce offspring, grow and develop, and adjust to changes in the environment. Sometimes nonliving things have one or more of these characteristics, but unless something has all of them it is not considered to be a living thing.

Are these alive?

These plants are called Lithops from the Greek lithos, meaning “stone.” Although they don’t appear to be so, Lithops are just as alive as elephants. Both species possess all of the characteristics of life.

HomeostasisHomeostasis is the regulation of an organism's

internal environment to maintain conditions suitable for survival. An example is the adjustment an organism makes in the amount of water in its cells; without the ability to make such adjustments, organisms die.

adaptationA structure, behavior or internal process that

enables an organism to respond to environmental factors and live to reproduce is an adaptation. Evolution is the gradual change of a species over time and occurs through adaptations.

Section 2

• The Nature of Science• To be science things must be testable!• Can you test the meaning of life?• The reason a dog sleeps on its back?• If one painting is better than another?

Section 2

• Vocabulary :• Science, theory, law, peer review, ethics.

science

• Knowledge based on the study of the natural world!

• This knowledge is obtained using scientific methods and inquiry to develop explanations of how things work. It is a very creative process and requires a very unbiased mind!

SCIENTIST

• When you think of a scientist, what words come to mind?

• DOES THE WORD CREATIVE COME UP?

• WELL, IT SHOULD!!!!

• Observant is another that is very important!

Alexander FlemingAlexander Fleming stumbled upon the

antibiotic partly by accident in 1928.

During routine research he noticed a mould called penicillium had developed on a plate, killing bacteria he was growing nearby.

He named the antibacterial substance penicillin.

But it was another 12 years before the drug's properties were investigated further.

Photo credit: National Media Museum/SSPL

Pseudoscience

• False• Science• uses some science and some things that

are not testable!• Astrology for example.• Claims that are untested by scientific

methods are pseudo science.

theory • A theory is an explanation of a natural

phenomenon that is supported by a large body of scientific evidence obtained from many different investigations and observations.

• It is NOT just a prediction or a guess about how something might work!!!

• What are some current scientific theories?

Law

• Laws explain relationships under specific conditions in nature. These usually can be tested or observed whereas theories explain much larger amounts of information and cannot be observed or “seen” even if we can support them with evidence we can never “prove” them.

• Laws do not become theories and theories do not become laws!

Laws• Newton's law of universal gravitation (Sir I. Newton)

Two bodies attract each other with equal and opposite forces; the magnitude of this force is proportional to the product of the two masses and is also proportional to the inverse square of the distance between the centers of mass of the two bodies; mathematically, F = (G m M/r2) e, • thermodynamic laws • First law of thermodynamics

• The change in internal energy of a system is the sum of the heat transferred to or from the system and the work done on or by the system.

• Second law of thermodynamics • The entropy -- a measure of the unavailability of a

system's energy to do useful work -- of a closed system tends to increase with time.

Science is always changing!

• As new information is observed we make changes to our theories this is what makes science so dynamic and interesting.

• Scientists welcome debate about theories!• Scientists question observations that do

not fit with what they already have seen.

Peer Review

• Before publishing work it is checked and rechecked by other scientists to make sure the work is valid and reliable. This is called peer review.

• Other scientists can review the work that is published and continue to evaluate its credibility.

• Journals that have peer review are the most reliable sources for scientific information.

Why is scientific literacy important?

• Today there is much information about medical and environmental issues in the news that have a strong scientific basis. It is important to be able to understand the issues and make the correct choices about them.

Ethics• Moral principles and values.

• There are several scientific issues that evoke strong ethical issues.

• They include:• Stem cell use, genetic engineering,

euthanasia and cryonics. • Even conducting proper scientific methods

requires ethics!

Explain how ethics are part of scientific discoveries.

Ethics are a system of moral values or principles of right conduct. The knowledge gained through scientific research is not good or bad, but some applications of scientific knowledge may be considered unacceptable to some people. It is the responsibility of society as a whole to determine the ethical use of scientific discoveries.

Stem cells

• How does technology benefit a society?

Technology is the application of scientific research to society's needs and problems.

It can result in improvements in such areas as food production, waste and pollution reduction, and medical care.

While technology has provided numerous benefits, sometimes problems result as well.

Section 3

• Vocabulary (7): observation, inference, scientific method, control group, experimental group, independent variable, dependant variable,

Ask a question about the real world!

• Try to find the answer using the scientific method!

scientific methods.• The common steps that biologists and

other scientists use to gather information and answer questions are collectively known as scientific methods.

• 1. observe, 2. question, • 3. make a testable explanation, • 4. experiment, 5. collect and

analyze data, 6. state findings

1.pose questions about the natural world, 2.conduct systematic observations, 3.examine books and other sources of

information to see what is already known, 4.review what is known in light of empirical

evidence, 5.plan investigations,

6. use tools to gather, analyze, and interpret data (this includes the use of measurement in metric and other systems, and also the generation and interpretation of graphical representations of data, including data tables and graphs),

7. pose answers, explanations, or descriptions of events,

8. generate explanations that explicate or describe natural phenomena (inferences),

9. use appropriate evidence and reasoning to justify these explanations to others,

10.communicate results of scientific investigations, and evaluate the merits of the explanations produced by others.

• These are the true steps of science.• Each of these could take minutes to years

in order to complete, depending on the topic!

• Being observant and creative are important characteristics of a good scientist!

• Where in the process do these traits help?

Types of observations• Qualitative and Quantitative• What is the difference?

• Qualitative means describing something such as its color, shape or texture

• Quantitative means using measurements such as its height, mass or volume.

Describe a bubble, make observations

Now lets do an activity to test your observational skills.

1. Write your name on a piece of paper.2. Make a bubble3. Write down observations, mark them as

D= qualitative or # = quantitative 4. Observe another person’s bubble and see if

you agree with their observations and could identify their bubble based on their observations…

Answer these questions:1. What type of observations are the easiest to

make?2. What type of observations would be the most

helpful to someone else trying to identify your bubble?

3. Which type of observations have the most room for opinion?

4. Which type of observations do scientist most often try to use in their research projects?

5. Why?

• Scientific methods usually begin with scientists identifying a problem to solve because they observed the world around them.

1. observe, 2. question• A hypothesis is an explanation for a

question or a problem that can be formally tested.

3. make a testable explanation

• Eventually, the scientist may test a hypothesis by conducting an experiment.

4. experiment 5. collect and analyze data• The results of the experiment will help the

scientist draw a conclusion about whether or not the hypothesis should be accepted or rejected.

6. state findings

Share the results

• Publishing a Paper– Scientists submit research papers to scientific

journals for publication.– In peer review, the editors of a journal will

send submitted papers out to experts in the field who anonymously read and critique the paper

– The scientific method involves making observations, asking questions, forming hypotheses, making predictions, designing experiments, analyzing data, and drawing conclusions.

What is a controlled experiment?

• Some experiments involve two groups: the control group and the experimental group.

• The control is the group in which all conditions are kept the same.

• The experimental group is the test group, in which all conditions are kept the same

except for the single condition being tested.

independent variable,• The condition in an experiment that is

changed is the independent variable, because it is the only variable that affects the outcome of the experiment.

Independent= X (amount of fertilizer)

dependent= Y (height)

Fertilizer amount

Height of plant

X

Y

dependent variable,• While changing the independent variable,

the scientist observes or measures a second condition that results from the change.

• This condition is the dependent variable, because any changes in it depend on changes made to the independent variable.

A scientist conducts an experiment to test the effect of light on plant growth. In each experiment, three plants of the same variety are each given 10 mL of water. One plant is exposed to full sunlight for 8 hours, one is exposed to full sunlight for 4 hours, and one plant is kept in a dark room. Plant height is measured after two weeks. What is the independent variable in this experiment?

What is the independent variable in this experiment?

The independent variable is the condition that is changed.

In this case, the amount of sunlight is changed for each plant.

Plant heights are measured results of the experiment, so plant height is the dependent variable.

Explain the difference between quantitative and qualitative information.

Video on graphs and data

• http://education-portal.com/academy/lesson/how-to-read-scientific-graphs-charts.html

Quantitative information can be expressed numerically, and may also be used to generate graphs or tables in order to communicate data clearly. Qualitative information is not expressed numerically. Observational data and written descriptions of what scientists observe, are qualitative information.

Experimental design

Bubbles!

Title

• Your choice• It should have something to do with your

experiment

Problem or purpose• What are your trying to find out?

Something to do with the bubbles?Brands?Things added to the solutions? Question is narrowly focused and suggests

how an answer might be investigated. It is answerable.

Does your problem…

Correctly identify specific, measurable independent and dependent variables?

Hypothesis

• Hypothesis is testable and clearly• stated in “If… then…” format.• Specifically predicts relationship• between dependent and independent

variables.

MaterialsComplete, detailed list of materials (size, conc., quantity)

presented in vertical list format

Procedure• A detailed list of exactly what you did.

Procedure cont.

Accurately tests the hypothesisConducts or analyzes at least 3 trials.Procedure is in vertical listformat, accurate, complete, easy to-follow, and reproducible byanother person.

Includes diagrams to clarify proceduresIncludes all appropriate safety concerns.

Data• Chart the

findings • Record

observations as the experiment is happening.

• observations

1floated, started to break down at 2 min

2

3 4

• Data table contains accurate, precise raw data & summary data reported in correct SI units with descriptive title.

• Data summarized in well organized, easy-to-read graph &/or figures.

• Descriptive title, appropriate labeling, keys, etc.

• Data summarized in a clear,concise, logical manner Patterns identified & described, but no conclusions drawn.

Cost of soap

• Ajax:  $1.87 – 30 oz• Dawn:  $2.83 – 24 oz• Great Value:  $1.97 – 24 oz • Palmolive $2.64 – 25 oz• Gain $1.97 – 30 oz

Data Analysis

• Organize the data: graphs , charts, ranges, mean, median, mode etc.

conclusion• Scientifically valid, logical conclusion, well

supported by the data collected. • Clearly addresses problem and stated hypothesis.

• Sources of error identified and explained. Appropriate recommendations made to eliminate errors.

• Student generates specific questions for future study.

Conclusion• How do the results relate to the original

problem?• What were some possible errors in your

procedure? Timing? Temp? Number of repetitions? Amount of water? Control? Was there only one variable?

• How could this experiment be improved?• Extensions: How could this info be useful in

real life? What might it mean? Does it make you come up with another hypothesis?

Share your Results• Turn in your formal write up.• For this lab :• Title• Problem• Hypothesis• Claim• Evidence: written and graph• Justification

Formal Lab Report

• The following are parts of most formal reports…

LAB REPORT FORMAT

• Note: all lab reports are to utilize this format (discrete sections, labeled as below, are mandatory). Reports are to use formal language; avoid using the words ‘we’, ‘I’, ‘us, ‘our’, etc. The report should have a title, your names, the date, and your class period. Conserve paper! Use both sides and eliminate unnecessary extra spacing.

INTRODUCTION• I. Describe the general rationale for your

investigation (Why is this being done? Why is this an important study? What can we learn or apply from this?).

• -Provide all appropriate background information for reader.

• -Clearly state the purpose of your investigation.

• -State hypothesis or hypotheses (null and alternative are often appropriate

Materials and Methods (Procedure)

• II. -List the materials used in your investigation.

-List (and describe, if appropriate) the procedures employed. This should be in list form, NOT a paragraph. Do not describe standard techniques such as massing or transferring fluids.

Remember that your goal is to provide sufficient information so that your investigation: 1. can be readily reproduced 2. can be evaluated for errors, limitations, etc. so that any conclusions can be assessed for believability (confidence).

• -If the procedure was provided prior to your investigation, you may simply attach it to your report. It is important to describe any changes which may have occurred from this protocol.

III. RESULTS •   -Present all data in clear and concise forms (at

times, graph paper or other materials may be provided for this purpose). If calculations are involved, show all work or work through one problem to illustrate.

• -Make certain that all charts, graphs, tables, etc. are clearly titled and labeled.

• -Highlight trends or significant results for the reader (do not repeat all data in prose form).

• -This section may also include a statistical analysis of your data.

IV. CONCLUSIONS -Evaluate data in light of your hypothesis. Be

careful with your choice of words; avoid the word prove!

• -Interpret and analyze your data for the reader. Offer possible explanations or reasons for your obtained data.

• -In light of your materials and procedure, evaluate your experiment. Describe the sources of possible error or the limitations of your materials or procedure. Suggest means of reducing these errors. Suggest improvements and include suggestions for further possible studies (how could this study be extended to provide relevant information?).

score topic Advanced (5) Proficient (3) Needs Improvement (1)

Question Question is narrowly focused and suggests how an answer might be investigated. It is answerable.

Question is answerable but not narrowly focused.

Question is too broad and not practically investigated.

Identificationof Variables

Correctly identifies specific, measurable independent and dependent variables.

Identifies variable being tested & variable being measured. .

• Variables and constantssignificantly incomplete &/orinaccurate.

Hypothesis Hypothesis is testable and clearlystated in “If… then…” format.Specifically predicts relationshipbetween dependent and independent variables.

Hypothesis is clearly stated. Itpredicts the influence of one variable on another.

Hypothesis is poorly stated anddoesn’t directly mention thevariables.

Materials Complete, detailed list of materials (size, conc., quantity) presented in vertical list format

Most materials are listed and appropriate.

Materials quite incomplete or inappropriate for experiment.

Procedure Accurately tests the hypothesis Attempts to test hypothesis Does not address hypothesis.

Conducts or analyzes at least 3 trials. Multiple trials attempted or need is recognized.

Single trial, poor understanding of use of multiple trials.

Procedure is in vertical listformat, accurate, complete, easy to-follow, and reproducible byanother person. Includesdiagrams to clarify procedures

Step-by-step procedure, generallyComplete. Minor errors/omissions make it difficult tofollow or not always repeatable

• Procedure difficult to follow Major omissions or errors.

• Includes all appropriate safety concerns. Includes critical safety concerns

Safety concerns trivial or inadequately addressed.

DataCollection &Presentation

Data table contains accurate,precise raw data & summary datareported in correct SI units withdescriptive title.

Data table with accurate data,most units labeled or implied.Minor errors. Title absent ortrivial.

Data table inaccurate, confusing,and/or incomplete. Missing units.

Data summarized in well organized,easy-to-read graph &/or figures. Descriptive title, appropriate labeling, keys, etc.

• Data displayed in well organized easy to read graph &/or figures.Descriptive title, minor errors in use of units and labeling.

• Graph/figures presented in aconfusing and/or sloppy fashion.

Data summarized in a clear,concise, logical manner Patterns identified & described,but no conclusions drawn.

Reasonable, but somewhatunclear summary of data.Patterns in data not clearlyidentified.

• Summary is unclear and illogical.Patterns in data not identified.

Conclusion Scientifically valid, logicalconclusion, well supported by thedata collected. Clearly addresses problem and stated hypothesis.

• Scientifically valid, logicalconclusion, supported by datacollected. Attempts to addressproblem and stated hypothesis.

Conclusion is incomplete orillogical. Does not address theproblem and hypothesis.

Sources of error identified andexplained. Appropriate recommendations made to eliminate errors.

• Sources of error identified Weak/trivial attempt to identifysources of error.

Student generates specificquestions for future study

Student makes attempt togenerate questions for futurestudy.

Student makes incomplete orinappropriate attempt to extend or apply knowledge.

Penny Lab!

The Scientific Method

“The Penny Lab”

The Scientific Method• Observations lead to questions and help

answer them.• The better the observations the more helpful

they are.• 2 types: • Qualitative that describe things

And• Quantitative that use numbers to measure…

• Observations lead to questions…• like “what would happen if…”• Or• “Why does this happen?”

• Background research is done to find our more about the subject.

• Maybe the answer is already known.• Information about the materials in the research

will help the scientist understand how they work better.

Hypothesis

• After researching the problem, and sometimes doing preliminary experimentation or reading about other scientists research a hypothesis is formed.

• Sometimes called an “educated guess” it really is more then a guess! Scientist put a lot of thought into their hypothesis.

• It will either be accepted or rejected by their own experimentation.

Controlled Experiment

• The scientist designs an experiment to test one variable at a time. This requires everything to be held the same except for the independent variable, the item being changed and tested. The thing that changes in the experimental groups is the dependent variable.

• This is called a controlled experiment.

• So if I were to add fertilizer to plants, and keep everything else the same, the fertilizer is the independent variable.

• If the plants were then measured to see if they changed in height, the height change would be the dependent variable.

• The groups with no fertilizer would be called the control group.

• You would compare the group with fertilizer to the control to see if any difference in growth occurred.

Collect Data• Quantitative observations are less subjective.• Data needs to be large in number to be valid• Many repetitions • Use math to analyze the data• mean, mode, median• Graphs show trends better.

Redesign the experiment

• Data collection may lead to the experiment needing to be redesigned.

What do you observe?

Water — "the stuff of life."

• 2 Hydrogen atoms and • 1 Oxygen atom

• Covalent bondsHold the Hydrogen toThe oxygen bySharing electronsUnevenly.

Hydrogen bonds

• Hydrogen bonds hold the water molecules to each other.

cohesion• Water is attracted to other water. • This is called cohesion.

• Surface tension is the name we give to the cohesion of water molecules at the surface of a body of water

Capillary action• Capillary action however, is related to the

adhesive properties of water. You can see capillary action 'in action' by placing a straw into a glass of water.

Hydrogen bonds

• The thermal properties of water are also linked to its hydrogen bonds. Water has a very high specific heat capacity, which is the amount of heat per unit mass required to raise its temperature by one degree Celsius. The energy required to raise the temperature of water by one degree Celsius is 4.2 joules per gram.

• Water also has a high heat of vaporization, which means that it can take a lot of heat without its temperature rising much. This plays a huge part in the climate, because it means that oceans take a long time to warm up.

solvent• Water is often known as the universal

solvent, which means that many substances dissolve in it.

Hydrogen bonds

What do Pennies have to do with this?

• And an eye dropper?

Your task…• Using the scientific method, ask a question,

use the background information on water I have provided you and develop a question, a hypothesis and then design a controlled experiment. Get your design approved and carry it out. Remember to test it more then one time! Collect your data and analyze it. Come to a conclusion. Accept or reject your hypothesis. Let your research lead you to another question. If time permits, test that one as well.

• Share your results with your colleagues. How does your data compare?

Steps to know!1. pose questions about the natural world, 2. conduct systematic observations, 3. examine books and other sources of information to see what

is already known, 4. review what is known in light of empirical evidence, 5. plan investigations, 6. use tools to gather, analyze, and interpret data (this includes

the use of measurement in metric and other systems, and also the generation and interpretation of graphical representations of data, including data tables and graphs),

7. pose answers, explanations, or descriptions of events, 8. generate explanations that explicate or describe natural

phenomena (inferences), 9. use appropriate evidence and reasoning to justify these

explanations to others, 10. communicate results of scientific investigations, and evaluate

the merits of the explanations produced by others.

• SI Units • The International System of Units[1]

(abbreviated SI from French: Système international d'unités[2]) is the modern form of the metric system and is generally a system of units of measurement devised around seven base units and the convenience of the number ten

Basic units in SI Volume= litersmass= kilograms or grams length= meterstime = secondTemperature = KelvinAmount of substance = moleLuminous intensity = candela

Meters lengthSmaller than a meter! dm 10 in a meter 1 x 10-1

cm 100 in a meter 1 x 10 -2

mm 1000 in a meter 1 x 10 -3

micro mm 1x 10 -6

Nano meter 1x10 -9

Pico meter 1 X 10 -12

Larger than a meter! Kilo meter 1 x 10 3

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